Set is python built-in data type, all elemens are unique in it. In this tutorial, we will introduce its subtraction operation for python beginners.
Python set data type
A python set looks like:
{1, 2, 3, 'c', 'a', 'b'}We can generate a set data as follows:
x = set(<iter>)
For example, we can create a set using python list, tuple or a string.
x = [1, 2, 3, "a", "b", "c"] print(set(x))
Python set subtraction operation
Set subtraction operation can remove some elements based on other set.
For example:
x = [1, 2, 3, "a", "b", "c"] print(set(x)) y = [2,3] z = set(x) -set(y) print(z)
Run this code, we will see:
{1, 2, 3, 'c', 'a', 'b'}
{'a', 1, 'b', 'c'}
If both A and B are set data, A-B means we will remove elements from A in B.